Loading machine



Dec. 20, 1938.

J. L. CLARKSON LOADING MACHINE 1935 2 Sheets-Sheet 1 Filed Oct. 26

JoH/v L. GLA E/(soN,

Dec. 20, 1938.

J. L. CLARKSON LOADING MACH I NE Filed Oct. 26, 1935 2 Sheets-Sheet 2c/O/M L. CLARA so 53 MK MW.

' broken up by the loading machine.

Patented Dec. 20, 1938 UNITED STATES PATENT OFFICE 14 Claims.

This invention applies to power-driven loading machines, such as areused for loading loose materials onto cars or trucks. While theinvention is applicable to machines of the loading type generally, themachine selected for illustration in the accompanying drawings and whichwill be described in the following specification as an embodiment of thepresent invention, is designed as a coal loading machine for loadingcoal in mines.

In the usual working of a coal mine in accordance with a system in wideuse in this country, the material is first separated from its bed in themine by blasting, or shooting as it is called. To accomplish thisoperation the vein of coal is first undercut along the floor of theentry. For this purpose, a kerf is cut horizontally along the floor by aspecial cutting machine designed for that purpose. This kerf usuallyruns back six or eight feet from the face of the working, and is usuallyabout six inches high. In some instances, a similar kerf is cutvertically through the middle of the vein. Shot holes are then drilledalong the top and sides of the vein, into which blasting powder isloaded and in due course exploded. This operation has the effect ofbreaking the coal loose from the vein along the top and sides so that itsettles down on the floor, the aforementioned horizontal kerf providingroom for such settling. The blast also has the effect of cleaving orcracking the coal along its cleavage planes throughout that portionwhich is separated from the vein. In this condition, the coal is readyfor loading on the mine cars.

The modern loading machine must be capable of attacking the coal in itsshot-down condition, loosening or cutting apart the fragments thereof,and gathering up and loading on the cars the broken mass of loosematerial. Furthermore, such gathering and loading must be carried out ata high speed so as to out down to a minimum the loading time per hour.In many instances the coal, upon being shot down, does not readily breakup into separate fragments but must be This is accomplished by thepresent machine by digging its way underneath the pile of shot-downmaterial. The digging and gathering head digs out the material frombelow the pile, gathers the same onto an elevating conveyor to becarried off, and keeps digging and working its way under the brokenpile. It is, accordingly, equipped with digging devices adapted to digaway the pile of material in such a manner as to permit entry of thehead of the machine underneath the pile.

One of the objects of this invention, therefore, is to provide a machinewith novel digging devioesadapted to clear a path underneath the pilefor the entry of the head of the machine.

Another object of this invention is to provide means to prevent lodgmentof material on the digging head in such a manner as to obstruct furtherentry of the head under the pile.

Another object is to provide novel means for adding to the digging andloading capacity of the gathering head.

Further objects will appear from the following description taken inconnection with the ac companying drawings, in which- Figure 1 is a planView of the front end of a loading machine embodying this invention,showing the gathering head thereof;

Figure 2 is a side elevation of the same;

Figure 3 is a sectional View, taken on line 3-3 of Figure 1.

I Figure 4 is a plan View similar to Figure 1, taken on line 44 ofFigure 5, illustrating another embodiment of this invention.

Figure 5 is a side View similar to Figure 2, but partly in section onthe line 5-5 of Figure 4.

Figure 6 is an enlarged detail of the front of the shoe seen in a Viewfrom the side similar to Figure 5.

Figure '7 is a detail section taken on linefl-J of Figure 4.

The general structure of a loading machine of this character ordinarilycomprises a traveling truck, which may be of the caterpillar tractortype or which may be arranged to run on tracks. This traveling truckusually carries the entire structure. An elevating conveyor extendsforwardly and downwardly from the traveling truck and functions to liftthe material over the structure of the truck itself and deliver it to asecond conveyor, usually carried at the rear of the truck. This secondconveyor ordinarily extends rearwardly from the truck and is adapted todeliver the material to the mine cars. The front end of the front orelevating conveyor is usually equipped with a gathering head whosefunction it is to gather up the material and load it onto the elevatingconveyor. For a detail description of a loader of this type, referencemay be had to the patent to John L. Clarkson, No. 1,904,355, issuedApril 18, 1933.

In the accompanying drawings, only the forward end of the elevatingconveyor is shown with its gathering head. The supporting structure ofthis elevating conveyor is indicated at I in the drawings, and theconveyor itself at 2. The conveyor 2 may be of any suitable type, thatshown in the drawings consisting simply of two side chains connected byhorizontally extending flights. The conveyor as a whole is arranged toslide upwardly along a trough member 3 carried by the supportingstructure l.

Mounted on the forward end of the elevating conveyor is a gathering head4. This is shown in the form of a flat plate or shoe adapted to form ashovel at the front end of the elevating conveyor and mounted so as toextend down to the ground in front of the conveyor and extendingupwardly and rearwardly so as to overlap the front end of the elevatingconveyor; The middle portion of this shoe or head is cut away so as toform a wide notch extending forwardly from the rear edge of thegathering head, the forward edge of this notch being indicated at 5.This notch is provided in order to expose the conveyor 2 for delivery ofthe material thereto. It will be noted, from Figure 2, that thegathering head 4 is arranged at a steeper inclination than the elevatingconveyor 2, the angular elevation of the shoe above the conveyor beingindicated at A. The purpose of this angular elevation will be explainedhereinafter. The supporting structure I may be equipped with a shaft oraxle 6, upon which may be removably mounted suitable road or trackwheels, as indicated by the broken line i, for transporting the machinefrom place' to place.

Suitably journaled on each side of the support I is a drive shaft 8,carrying at its upper end sprockets 9 and I and connected at its lowerend by bevel gears II and I2 with a transverse shaft l3 carrying asprocket |4 driven by a chain 5 or other suitable drive from a maindrive shaft I6. The main drive shaft l6 may itself be driven in anysuitable manner from a motor, usually mounted on the traveling truck.These driving connections are not shown in the drawing. The sprocket 9is arranged to drive a. gathering chain equipped with suitable gatheringarms or picks 18. At its lower end the chain l1 passes around a sprocketi9 loosely carried by a stub shaft 20 supported in the structureGathering chains I? are arranged in duplicate, one on each side of theconveyor 2, as seen in Figure 1. The arrangement is such that whendriven in their normal operation, the chains travel in'orbital paths onthe head 4, as defined by the sprockets 9 and I9. The direction ofmovement is upwardly at the inner portion of their travel over theconveyor 2, as indicated by the arrows in Figure 1.

The chains I7, with their picks, which travel in corresponding orbitalpaths over the head or shoe 4, provide means for gathering the materialfrom the ground and progressing it over the lower end of the shoe andonto the conveyor 2. The movement of the picks i8 is such that at thelower portion of their movement, where they pass around the lowersprocket l9, they extend beyond the end of the shoe 4 down to the groundand serve to pick up or loosen and cut away the material in front of theforward edge of the shoe 4. The picks on opposite chains are interspacedwith reference to each other so that they pass in front of the shoealternately. They are arranged so that their paths cross beyond the endof the shoe, and therefore they scrape the ground in front of the entirefront edge of the shoe. This action serves not only to pickup allmaterial from in front of the shoe, but also to cut away any lumps orhigh places which may protrude above the normal level of the ground infront of the shoe. This is important as it acts to continually cut downthe floor of the mine in front of the machine to a constant level andthereby maintains the normal floor level for the mine.

Mounted above each of the gathering chains I1 is a cover plate 2|. Thisplate serves to guide and protect the chains and prevent material fromfalling between them. The plate 2| may be supported by a longitudinalweb 22 joined at its ends to transverse webs 23, the whole beingpreferably welded together, and to the plates 2| and 4. These webs serveto stiffen the cover plate and to support it against the strain ofmaterial falling thereon.

In the operation of the gathering mechanism, the picks l8, movingthrough their orbits as indicated in Figure 1, sweep the ground in frontof the front edge of the shoe 4 and gather the material and pass it uponto the front portion of said shoe between the two chains. The picksthus operate to progress the material over the shoe and deliver it overthe edge 5 to the conveyor 2, which carries it upwardly over thetraveling truck and delivers it to the second conveyor, which in turndelivers it to the mine cars as already explained. The machine may besuccessfully operated in this manner and will be effective in loadingcoal or other loose material at a rapid rate. Where coal has been shotdown, as already explained, the machine so equipped will dig its wayunder the pile and carry out and load the loose coal. During suchoperation, the gather head often enters to a considerable distanceunderneath the pile, occasionally to such an extent that the entiregathering head is submerged. It occasionally happens, however, that theshot material does not fall readily when loosened by the gatheringmechanism, but remains suspended above the gathering head. It has beenfound also that loose materials sometimes accumulate on the top of thecover plate 2| in a position where the picks l8 cannot reach them. Undersuch conditions, a pile of loose material lodged on top of the coverplate 2| may, when the head is worked under a pile of tight material,come into engagement with the material suspended above the gatheringhead and thereby prevent further 1 progress of the head under the pile.

In order to prevent this action, the present machine is equipped with asecond pair of chains 24, one of which is mounted to travel in anorbital path on top of each of the cover plates 2|. These chains arealso equipped with picks which travel in orbits similar to those of thepicks l8. This upper chain is driven by a sprocket ID on the drive shaft8 and passes at its lower end over an idler sprocket 25 also looselymounted on the shaft 20. A second idler sprocket 26 guides the chain 24inwardly to a point'such that the material handled by this chain isdelivered to the conveyor 2. The sprocket Hl may be made of any desiredsize relative to the sprocket 9, and the relative speeds of the chains24 and I1 will correspond to the relative sizes of these sprockets.These speeds may be given any desired value, but it is usually desirableto have them run at about the same speed, or to make the upper chain 24travel a little slower than the lower chain M. It will be noted that,since the lower sprocket 25 of the clearing chain is relatively small indiameter, the picks 21 and 28 will pass around this sprocket at arelatively high speed. Accordingly, at this point these picks areactuated to deliver a sharp digging blow which is very effective inbringing down tight material.

The function of the chain 24 is two-fold. It is equipped with scrapingor digging picks 21 and also with upstanding picks or horns 28. Thepicks 21 operate to sweep the loose material off the cover plate 2| andalso to assist in digging new material from the working face. Theupstanding picks 28 assist in these operations and also attack thematerial which may be suspended above the gathering head and operate toloosen or cut down that material so that it may be gathered and loadedby the machine. The chain I! may also be equipped with upstanding hornsor picks 29 which assist in the digging operation and also in cuttingthe suspended material above the gathering head. This arrangementenables the machine to cut its way into a pile of material, clearing allthe material in front of it and even above it, and operating to gatherthis material onto the conveyor 2 and to load it onto the mine cars orother receptacles. The gathering head may thus work its way under tightcoal, which refuses to fall but remains suspended above the machine. Byattacking this suspended coal with the picks 28 and 29, said material isloosened and brought down upon the gathering head and is then gatheredand loaded along with the rest of the material.

The usual conditions of operation in a coal mine are indicated in Figure3, in which the dotted line 30 represents the working face of tight coaland the line 3I represents the lower surface operated on by the machineas it enters underneath the suspended material. The line 32 representsthe floor line. As the operation proceeds, the picks I8, 29 and to someextent the picks 2T, dig away the material in front of the shoe 4 andgather it onto the conveyor 2. As the head enters under the pile, thepicks 28 and 29 come into play in operating upon the suspended materialat the surface 3I. Thus the digging operation takes place both in frontof and above the gathering head simultaneously. The chain 24, with itspicks, at the same time provides a clearing device to clear theaccumulated material away from on top of the cover plate 2 I. A narrowtop plate 33 may be provided to cover and protect the chain 24.

The conveyor 2 may be driven from the drive shaft I6 by sprockets 34engaging the side chains of the conveyor. The cross shaft I3 may be madein two sections, as illustrated in Figure l, the sections beingconnected by a flexible coupling 35 to allow for misalignment of the twosections of the shaft under flexure of the support I, such as may occurwhen the head is unevenly loaded with material or obstructions areencountered in the operation thereof. The separate sections of the shaftI3 may, however, be entirely separated and individually driven by thechains I5. Suitable means, not shown in the drawing, are provided forraising and lowering the support I and for swinging the same laterallyfrom side to side so as to provide for manipulating the gathering head,in order to reach ma-' terials in different positions with relation tothe traveling truck.

In the operation of this machine, the traveling truck is operated tocarry the machine to the desired point at which operations are to becarried out. The support I is manipulated on the traveling truck so asto present the gathering head 4 to the pile of material. The truck isthen advanced so as to push the head against the pile of material. Atthe same time the shaft I6 is operated so as to drive the chains II and24 and also the conveyor 2. Upon operation of the chains, the picksthereon become active in cutting loose and gathering the material asalready described. This material is passed on to the conveyor 2, whichcarries it away to be loaded on to the mine cars. It is desirable todrive the conveyor 2 at a somewhat higher speed than that of the chains24 and II. This accomplishes several advantageous results. It providesthat all the material gathered will be promptly carried away anddisposed of soas not to choke the gathering mechanism. At certain timesin the operation of the machine, after the gathering head has cut itsway under a pile of tight material, the material gives way and theentire mass falls upon the machine. Under such circumstances, a highspeed of travel for the conveyor 2 is effective in carrying away thefallen material very rapidly, and this prevents the establishment of adeep pile of material upon the gathering head at the point where thepicks I8 turn outwardly in their travel at the upper end of their orbit.If this outward turn were carried out under a deep pile of material,there would be danger of throwing most of this material off the machine,and this effect is prevented to a large extent by the extra speed of theconveyor 2 in carrying away the fallen material.

The increased elevation of the gathering head over that of the conveyor2, as represented by the angle A, is also effective in clearing thepicks before they turn outwardly to their return path. By virtue of thisangle, the picks move in a path which rises with respect to the conveyor2, and

at their outward turn are spaced well above that conveyor so as to freethe material carried thereby. This also prevents the effect of throwingthis material off the machine.

It will be seen therefore that the arrangement is such that the machinenot only gathers and loads the material which may be in front of it, butis capable of digging its way under a pile of tight material. Thelodgment of loose material on top of the gathering chain is prevented bythe operation of the clearing chain 24, so that any liability toobstructing the movement from this source is eliminated. Furthermore,means are provided for actually attacking overhanging material so as tobring that material down upon the gathering mechanism to be gathered andcarried away for loading along with the rest of the material.Accordingly, practically every obstruction to the advance of the machineis eliminated by the action of this improved mechanism. It will also benoted that while the chain 24 is primarily a clearing device to preventobstruction of the chain II, it also has a gathering function of its ownand co-operates with the conveyor 2 by supplying material thereto. Whilethe orbit of the chain I1 is broad at its lower end so as to provide anample sweep for the picks I8 in .order to clear the front edge of theshovel, the

corresponding portion of the orbit of the chain 24 is narrow, so as toavoid accumulation of any serious amount of material thereon.

In the embodiment of Figures 4 and 5, a modified arrangement of theclearing chain 24 is illustrated. In this case the clearing chain doesnot run the full length of the top plate 2I, but extends only betweenthe sprockets 25 and 26. This shortens the chain 24 and adds materiallyto its strength. Its clearing function is not impaired as it has beenfound that in most cases it is necessary to clear only the lower end ofthe plate 2I.

In the embodiment of Figures 4 and 5, the clearing chain 24 is drivenfrom the gathering chain H. The gathering chain driven by the shaft 8functions itself to drive the sprocket l9 and thereby, through a commonsleeve turning on the stub-shaft 20, the sprocket 25. The sprocket 25drives the chain 24. It will be noted that the direction of travel ofchains H and 22 i, is the same so that the picks on both chains moveupwardly at the inner portion of their orbit.

The sprocket 25 is set near the inner edge of the plate 2i so that thepicks 21 on the chain 2 5, tend to carry the material inwardly anddeliver it to the conveyor 2 in a manner similar to that of the picksii! of the gathering chain II.

It has been found that in some cases when the gathering chain ii becomesworn the picks i8 may have a tendency to sag. During the greater part oftheir travel these picks are supported upon the head 6. However, as theyturn about the lower sprocket l9 they extend beyond the end of the headi and at this point any tendency for a pick to sag, may cause it tointerfere with the rail 48 on which the loading machine runs. Suchinterference between the pick and the rail while the pick is in motion,may tend to throw the head of the machine to one side.

In order to overcome this defect, a curved supporting rail or ridge 4!is provided at the point where the gathering chain turns about the lowersprocket Is. This rail may be formed of a simple strip or bar ironwelded or otherwise secured to the head 4. In the arrangement shown inFigures 4 and '7 the rail 4i is welded to the head i. The weld iscarried out in such manner as to provide an inner-bevel ifi extendingalong the inner-curve of the rail 46 to provide a bearing for the rearportion of the pick 58, as it passes around the lower sprocket As thepick passes over this rail 4!, its outer end is elevated as shown'inFigure 6, so as to clear the rail 48. The upper end of the rail 4!, isprovided with a rising approach as indicated at 33.

While this invention has been described as embodied in a unitary device,it will be understood that individual features and sub-combinationsthereof may be novel and useful of themselves without reference to therest of the combination. It is understood that the'employment of suchindividual features and sub-combinations is contemplated by thisinvention and within the scope of the appended claims. It is furtherobvious that various changes may be made, within the scope of theappended claims, in the detai s of construction without departing fromthe s; of this invention; it is to be understood t1 refore, that thisinvention is not limited to the specific details shown and/or described.

Having thus described the invention, what is claimed is:

1. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a

gathering head extending upwardly and rearwardly to overlap saidconveyor and having a way therealong, a gathering chain moving on saidhead in a path extending upwardly and rearwardly and having picksadapted to gather the material and progress the same over said way andonto said conveyor, and a clearing chain movabie in a path extendingupwardly and rearwardly above said gathering chain and having picksadapted to clear away material above said gathering chain.

2. In a loading machine of the character described having an elevatingconveyor at the front thereof, a gathering head overlapping saidconveyor and having a way therealong, a gathering chain movable in anorbital path on said head and having picks adapted to gather thematerial and progress the same over said way onto said conveyor, and aclearing chain mounted to move in an orbital path above said gatheringchain and having means to clear away the material above said gatheringchain.

3. In a loading machine of the character described having an elevatingconveyor at the front thereof, a gathering head overlapping saidconveyor and having a way therealong, a gathering chain movable in anorbital path on said head and having picks adapted to gather thematerial and progress the same over said way onto said conveyor, a coverplate for said gathering chain, and a clearing chain mounted for orbitalmovement on said cover plate and having means thereon to remove loosematerial from said plate and to loosen tight material suspended abovesaid head.

- i. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly to overlap saidconveyor and having a way therealong, a gathering chain moving on saidhead in a path extending upwardly and rearwardly and having picksadapted to gather the material and progress the same over said way andonto said conveyor, a cover plate for said gathering chain, and aclearing chain movable in a path extending upwardly and rearwardly abovesaid gathering chain and having means to remove loose material from saidplate and to loosen material suspended above said 5. In a loadingmachine of the character described, an elevating conveyor at the frontof the machine extending upwardly and rearwardly, a gathering headextending upwardly and rearwardly to overlap said conveyor and having away'therealong, a gathering chain moving on said head in a pathextending upwardly and rearwardly and having picks adapted to gather thematerial and progress the same over said way and onto said. conveyor, aclearing chain movable in a path extending upwardly and rear- Wardlyabove said gathering chain and having picks adapted to clear awaymaterial above said gathering chain.

6. In a loading machine of the character de scribed having an elevatingconveyor at the front thereof, a gathering head overlapping saidconveyor and having a way therealong, a pair of gathering chains havingpicks movable in paths leading inwardly toward each other beyond the endof said head, then upwardly over said way and extending along saidconveyor to progress the material thereonto, said chains then movingoutwardly away from each other to return paths, the paths of said chainsat their outward movement being spaced above said conveyor sufficientlyto free the material lumps thereon, and a clearing chain mounted aboveeach of said gathering chains to move in an orbit substantialiy paralleltherewith and having picks adap ed to clear the material from above saidgathering chain.

7. In a loading machine of the character described having an elevatingconveyor at the front thereof, a gathering head overlapping saidconveyor and having a way therealong, a pair of gathering chains havingpicks movable in paths leading inwardly toward each other beyond the endof said head, then upwardly over said way and extending along saidconveyor to progress the material thereonto, said chains then movingoutwardly away from each other to return paths, the paths of said chainsat their outward movement being spaced above said conveyor sufficientlyto free the material lumps thereon, a cover plate for each of saidgathering chains, and a clearing chain mounted for movement in anorbital path on said cover plate and having picks adapted to clear thematerial from said plate.

8. In a loading machine of the character described having an elevatingconveyor at the front thereof, a gathering head overlapping saidconveyor and having a way therealong, a pair of gathering chains havingpicks movable in paths leading inwardly toward each other beyond the endof said head, then upwardly over said way and extending along saidconveyor to progress the material thereonto, said chains then movingoutwardly away from each other to return paths, the paths of said chainsat their outward movement being spaced above said conveyor sufficientlyto free the material lumps thereon, a cover plate for each of saidgathering chains, and a clearing chain mounted for movement in anorbital path on said cover plate, and having sweeping and cutting picksadapted to clear the material from said plate and to loosen the materialthereabove.

9. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly to overlap saidconveyor and having a way therealong, gathering means moving on saidhead in a path extending upwardly and rearwardly therealong, and a.clearing chain movable in a path extending upwardly and rearwardly abovesaid gathering means and having an upstanding pick adapted to loosentight material suspended above said head.

10. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly to overlap saidconveyor and having a way therealong, gathering means moving on saidhead in a path extending upwardly and rearwardly therealong, a clearingchain movable in a path extending upwardly and reawardly above 55 saidgathering means, and upstanding picks on said gathering means and saidchain adapted to attack material suspended above said head.

11. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly to overlap saidconveyor and having a way therealong, a gathering chain moving on saidhead in a path extending upwardly and rearwardly therealong, upper andlower sprockets for said chain, and a clearing chain driven from saidlower sprocket to move along and above said gathering chain.

12. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly to overlap saidconveyor, a gathering chain moving on said head to gather and movematerial onto said conveyor, and a clearing chain moving above saidgathering chain in a path deviating from that of said gathering chainadapted to clear away material above said gathering chain and move thesame toward said conveyor.

13. In a loading machine of the character described, having an elevatingconveyor at the front of the machine extending upwardly and rearwardly,a gathering head extending upwardly and rearwardly with respect to thefront of said conveyor and having a way therealong, and gathering chainsmoving on said head and having gathering arms rigidly connected theretoto gather the material and progress the same over said way onto saidconveyor; means for preventing sagging of said arms where they extendbeyond said head comprising a rail extending along the lower portion ofthe path of said arms adapted to elevate the tips thereof suflicientlyto compensate for wear of their connections.

14. In a loading machine of the character described, an elevatingconveyor at the front of the machine extending upwardly and rearward-1y, a gathering head extending upwardly and rearwardly with respect tothe front 01 said conveyor, gathering means moving on said head in anorbital path extending upwardly and rearwardly therealong, and clearingmeans movable in av different orbital path of similar form to that ofsaid gathering means but spaced thereabove and having a digging pickadapted to loosen material suspended above said head and moving in apath to clear said gathering means of material falling thereon.

JOHN L. CLARKSON.

CERTIFICATE OF CORRECTION Patent No. 2,11 .1,1148. v December 20, 958.

JOHN L CLARKSON.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,first column, line 1 2, for the word "honr" read car; and that the saidLetters Patent shouldbe read with this correction therein that the samemay conform to the record of the case in the Patent, Office.

Signed and sealed this 7th day of February, A. D. 1959.

' Henry Van Arsdale.

(Seal) Acting Commissioner of Patents.

